[media] dvb-bt8xx: use goto based exception handling

Repeating the same cleanup code in each error handling path makes life
unnecessarily difficult for reviewers, who much check each instance of
the same copy+pasted code separately.  A "goto" to the end of the
function is more maintainable and conveys the intent more clearly.

While we're touching this code, also lift some assignments from "if"
conditionals for simplicity.

No functional change intended.

Signed-off-by: Jonathan Nieder <jrnieder@gmail.com>
Signed-off-by: Mauro Carvalho Chehab <mchehab@redhat.com>

drivers/media/dvb/bt8xx/dvb-bt8xx.c

@@ -744,57 +744,42 @@ static int __devinit dvb_bt8xx_load_card(struct dvb_bt8xx_card *card, u32 type)
 	card->demux.stop_feed = dvb_bt8xx_stop_feed;
 	card->demux.write_to_decoder = NULL;
 
-	if ((result = dvb_dmx_init(&card->demux)) < 0) {
+	result = dvb_dmx_init(&card->demux);
+	if (result < 0) {
 		printk("dvb_bt8xx: dvb_dmx_init failed (errno = %d)\n", result);
-
-		dvb_unregister_adapter(&card->dvb_adapter);
-		return result;
+		goto err_unregister_adaptor;
 	}
 
 	card->dmxdev.filternum = 256;
 	card->dmxdev.demux = &card->demux.dmx;
 	card->dmxdev.capabilities = 0;
 
-	if ((result = dvb_dmxdev_init(&card->dmxdev, &card->dvb_adapter)) < 0) {
+	result = dvb_dmxdev_init(&card->dmxdev, &card->dvb_adapter);
+	if (result < 0) {
 		printk("dvb_bt8xx: dvb_dmxdev_init failed (errno = %d)\n", result);
-
-		dvb_dmx_release(&card->demux);
-		dvb_unregister_adapter(&card->dvb_adapter);
-		return result;
+		goto err_dmx_release;
 	}
 
 	card->fe_hw.source = DMX_FRONTEND_0;
 
-	if ((result = card->demux.dmx.add_frontend(&card->demux.dmx, &card->fe_hw)) < 0) {
+	result = card->demux.dmx.add_frontend(&card->demux.dmx, &card->fe_hw);
+	if (result < 0) {
 		printk("dvb_bt8xx: dvb_dmx_init failed (errno = %d)\n", result);
-
-		dvb_dmxdev_release(&card->dmxdev);
-		dvb_dmx_release(&card->demux);
-		dvb_unregister_adapter(&card->dvb_adapter);
-		return result;
+		goto err_dmxdev_release;
 	}
 
 	card->fe_mem.source = DMX_MEMORY_FE;
 
-	if ((result = card->demux.dmx.add_frontend(&card->demux.dmx, &card->fe_mem)) < 0) {
+	result = card->demux.dmx.add_frontend(&card->demux.dmx, &card->fe_mem);
+	if (result < 0) {
 		printk("dvb_bt8xx: dvb_dmx_init failed (errno = %d)\n", result);
-
-		card->demux.dmx.remove_frontend(&card->demux.dmx, &card->fe_hw);
-		dvb_dmxdev_release(&card->dmxdev);
-		dvb_dmx_release(&card->demux);
-		dvb_unregister_adapter(&card->dvb_adapter);
-		return result;
+		goto err_remove_hw_frontend;
 	}
 
-	if ((result = card->demux.dmx.connect_frontend(&card->demux.dmx, &card->fe_hw)) < 0) {
+	result = card->demux.dmx.connect_frontend(&card->demux.dmx, &card->fe_hw);
+	if (result < 0) {
 		printk("dvb_bt8xx: dvb_dmx_init failed (errno = %d)\n", result);
-
-		card->demux.dmx.remove_frontend(&card->demux.dmx, &card->fe_mem);
-		card->demux.dmx.remove_frontend(&card->demux.dmx, &card->fe_hw);
-		dvb_dmxdev_release(&card->dmxdev);
-		dvb_dmx_release(&card->demux);
-		dvb_unregister_adapter(&card->dvb_adapter);
-		return result;
+		goto err_remove_mem_frontend;
 	}
 
 	dvb_net_init(&card->dvb_adapter, &card->dvbnet, &card->demux.dmx);
@@ -804,6 +789,18 @@ static int __devinit dvb_bt8xx_load_card(struct dvb_bt8xx_card *card, u32 type)
 	frontend_init(card, type);
 
 	return 0;
+
+err_remove_mem_frontend:
+	card->demux.dmx.remove_frontend(&card->demux.dmx, &card->fe_mem);
+err_remove_hw_frontend:
+	card->demux.dmx.remove_frontend(&card->demux.dmx, &card->fe_hw);
+err_dmxdev_release:
+	dvb_dmxdev_release(&card->dmxdev);
+err_dmx_release:
+	dvb_dmx_release(&card->demux);
+err_unregister_adaptor:
+	dvb_unregister_adapter(&card->dvb_adapter);
+	return result;
 }
 
 static int __devinit dvb_bt8xx_probe(struct bttv_sub_device *sub)